1. Field of the Invention
The present invention relates to an information projecting apparatus which houses a plurality of cartridges each of which contains an information recording medium, such as microfiche or roll microfilm.
2. Description of the Prior Art
Conventionally, this type of apparatus comprises a storage section which houses a plurality of cartridges each of which contains microfiche or roll microfilm as well as a retrieving mechanism which selects a desired cartridge from the storage section, automatically transports the film from this cartridge, retrieves a desired frame, and stops the same at a predetermined position, whereupon the frame of the retrieved film is projected onto the screen of a reader unit or onto copying paper or the like of a printer unit. A support for storing a plurality of cartridges at a projection station which is illustrative of prior art devices is shown in U.S. Pat. No. 3,674,347 which issued to Iha on Jul. 4, 1972.
With the information projecting apparatus according to the prior art, there is a delay between the time when a desired cartridge is selected and retrieved from the storage section and the time when the information on the film inside the cartridge is projected. Moreover, since the number of cartridges that can be stored is limited by the size of the storage section , it has not been possible prior to the present invention to increase the capacity of this type of information projecting apparatus. Another drawback with prior art equipment is the delay from the time the retrieved cartridge is returned to the original position of the storage section after using it to the time when the cartridge to be used next is retrieved. This makes it impossible to make use of the projecting section during this operation.